#include <iostream>
#include <string>

class Pig {
   private:
    const std::string name;
    int age;

   public:
    Pig(std::string n, int a);
    void say_hello() {
        std::cout << "I am " << this->name << ". I am " << this->age << " years old." << std::endl;
    }
    void grow_up() {
        age++;
    }
};
